Question

What are the inflection points for `f(x) = -x^4-9x^3+2x+4`?

Answer 1

f'(x)= `-4x^3 -27x^2 +2`

f"(x)= `-12x^2-54x`

Inflection points would be given by f''(x)=0, that is `-12x^2-54x`=0,

=-6x( 2x+9)=0
x= 0, `-9/2` are the inflection points.